The American Heart Association / American Stroke Association has published a scientific advisory which includes new oral anticoagulants to prevent stroke in patients with atrial fibrillation. For many years, the only oral anticoagulant available has been warfarin (Coumadin). Alternatives have now been introduced. Dabigatran (Pradaxa) was approved by FDA in October 2010, followed by rivaroxaban (Xarelto) in November 2011. This document also takes the unusual step of providing recommendations for apixaban (Eliquis), which has not yet been approved.
The newer agents share several things in common. Each of them appears to have a lower risk of brain hemorrhage compared to warfarin in the trials in which they were studied. The newer drugs do not require blood tests to monitor their dosing. They may require dosage adjustment based on age, weight, and kidney function. There are no definite antidotes. And they are each more expensive than warfarin.
The document does not recommend switching patients to the new drugs from warfarin if they have been well controlled for long periods of time and have remained stable. “The selection of an agent should be individualized on the basis of risk factors, cost tolerability, patient preference, potential for drug interactions, and other clinical characteristics”.
As each of these drugs is an anticoagulant, there is a risk of bleeding with each of them. But for many patients, the benefits of stroke prevention outweigh the risks of bleeding.
The advisory is published online in the journal Stroke August 2, 2012
You may access the advisory here